Base fabric coated with resin having mixture of quaternary ammonium germicides



United States Patent 3,247,058 BASE FAliRlC COATED WITH RESIN HAVINGMIXTURE 0F QUATERNARY AMMGNEUM GERMICIDES Sam M. Hyman, 1411 Ahrens St.,Manitowoc, Wis. No Drawing. Filed June 8, 1962, Ser. No. 200,945 6Claims. (Cl. 167-386) This invention relates to a material containing anactive germicide and more particularly to a plastic or rubber coatedfabric impregnated with a germicide.

This application is a continuation-in-part of copending applicationSerial No. 126,459, filed June 26, 1961, now abondoned.

The primary object of the invention is to provide a germicidally treatedmaterial for use in the control of pathogenic microorganisms. Thetreated material has particular use in hospitals, restaurants, dairies,laundries and the like where it is necessary to control and reducebacteria activity. More specifically, the material can be used forhospital and other laboratory purposes as draw sheets, laundry basketliners, laboratory aprons, hamper bags, mattress covers and the like,and also has domestic use as diaper bags, mattress covers, sweat suitsand other similar articles.

Accordingly to the invention, the germicidally treated article comprisesa base fabric coated with a thermoplastic resin or natural rubber.Finely divided particles of a germicide are dispersed within thethermoplastic material or rubber coating and the thermoplastic coatingnot only serves to hold or retain the germicide, but also presents asmooth surface which can be readily cleaned. The germicidal material tobe used is an organic ammonium quaternary salt, and it has been foundthat the combination of an alkyl dimethyl benzyl ammonium halide withthe alkyl group containing from 8 to 18 carbon atoms and a diisobutylphenoxyethoxy ethyl dirnethylbenzyl ammonium halide is particularlyeffective as the germicide. This combination of germicidal materialsprovides an effective protection against bacteria and othermicro-organisms, such as Staphylococcus aureus, Brucella abortus,Clostridium welchii, Proteus vulgaris, Pseudomonas aeruginosa,Salmonella choleraesuis, Salmonella typhosa, Streptococcus fecalis, andthelike.

As the germicidal material is dispersed within the thermoplasticcoating, the germicide will be retained in the material and be effectivefor long periods of time. The fabric can be repeatedly washed in eithercold or hot water and the germicidal effect will be relativelyunimpaired.

The fabric backing material can be any reinforcing material which willprovide the necessary tensile strength for the article and can take theform of fabric made of synthetic fibers, such as nylon, Dacron, Orlon orrayon; animal fibers such as wool; vegetable fibers such as cotton;ormineral fibers such as glass or asbestos; and the like.

The coating material can be natural rubber or any thermoplastic resin orelastomer which, in the cured state, is sufliciently flexible to permitthe composite article to be readily handled and fabricated. The coatingcan be applied as a natural rubber or synthetic latex in which theparticles of natural rubber or resin are suspended in a liquid carriersuch as water or other evaporable liquid. The latex can be applied tothe fabric back ing by spraying, dipping or the like, and subsequentlydried to form the smooth surface coating on the fabric backing.Butadiene styrene, butadiene acrylonitrile, neoprene, polyvinyl chlorideacrylic resins, and the like can be used to form the synthetic latex.

The thermoplastic resin coating can also be applied to 3,247,053Patented Apr. 19, 1966 the fabric backing by conventional spread-coatingprocesses. In this process the fabric passes over a table or counter andthen over a supporting roll. An adjustable coating knife or doctor bladeis located between the supporting roll and a following roll. The coatingmaterial, in a soft state, is introduced just behind the blade and theblade spreads a film of the coating material on the fabric. Thethickness of the film is determined by the adjustment of the blade andthe speed of travel of the fabric.

The particular method of applying the thermoplastic coating to thefabric backing is not critical to the invention and any method commonlyused for coating fabrics or similar sheet material can be employed.

The germicide, distributed as fine particles throughout the coating, isan organic ammonium quaternary salt in which the hydrogen atoms attachedto the nitrogen atom in the normal ammonium quaternary salt are replacedby organic groups. In general, the ger-micide may be an alkyl trimethylammonium halide with the alkyl group having from 8 to 18 carbon atoms, adialkyl dimethyl ammonium halide with the alkyl group having from 8 to18 carbon atoms, an alkyl dimethyl benzyl ammonium halide with the alkylgroup having from 8 to 18 carbon atoms, a diisobutyl phenoxy ethoxyethyl dimethylbenzyl ammonium halide, a diisobutyl cresoxy ethoxy ethyldimethylbenzyl ammonium halide, and mixtures thereof.

Typical germicides which can be used are Methyl dodecyl benzyl trimethyl ammonium chloride;

Methyl dodecyl xylylene bis-trimethyl ammonium chloride;

Alkyl trimethyl ammonium chloride with the alkyl group comprisingdodecyl and 9% tetradecyl and 1% octadecenyl;

Alkyl trimethyl ammonium chloride where the alkyl group comprises 90%hexadecyl, 6% octadecyl and 4% oc-tadecenyl;

Alkyl trimethyl ammonium chloride where the alkyl group comprises 8%octyl, 9% decyl, 47% dodecyl, 18% tetradecyl, 8% hexadecyl, 5% octadecyland 5% octadecenyl;

Normal alkyl dimethyl benzyl ammonium chloride where the alkyl groupcomprises 50% dodecyl, 30% tetradecyl, 17% hexadecyl and 3% octadecenyl;

Dialkyl dimethyl ammonium chloride where the alkyl group comprises 8%octyl, 9% decyl, 47% dodecyl, 18% tetradecyl, 8% hexadecyl and 10%octadecyl;

Dialkyl dimethyl ammonium chloride where the alkyl group comprises 24%hexadecyl, 4% octadecyl, 30% octadecenyl and 42% octadecadienyl;

Normal alkyl dimethyl benzyl ammonium chloride where the alkyl groupcomprises 50% dodecyl, 30% tetradecyl, 17% hexadecyl and 3% octadecyl;

Normal alkyl dimethyl ethyl benzyl ammonium chloride where the alkylgroup comprises 50% dodecyl, 30% tetradecyl, 17% hexadecyl and 3%octadecyl;

Alkyl dimethyl 3,4-chlorobenzyl ammonium chloride where the alkyl groupcomprises 50% dodecyl, 30% tetradecyl, 17% hexadecyl and 3% octadecyl;

Diisobutyl phenoxyethoxy ethyl dimethylbenzyl ammonium chloride;

Diisobutyl cresoxy ethoxy ethyl dimethylbenzyl ammonium chloride andmixtures thereof.

The corresponding bromides can be substituted for the chlorides in thequaternary salts set forth above. However, if a combination ofquarternary salts is to be used as the germicide, all of the germicidesin a given combination should either be chlorides or bromides and notmixtures thereof,

The germicide comprises about 5% to 25% by Weight of the thermoplasticcoating, based on active materials. In addition, a small amount in therange of .01% to 1.0% by weight of the coating of boric acid can beincluded to increase the adherence between the thermoplastic materialand the fabric, and from 0.01% to 1.5% of a defoaming agent, such as2-ethyl hexanol, can also be employed in the coating mixture to reducethe foaming action of the ger-micide during mixing and to prevent abubbly-type of coating.

It has been found that the combination of diisobutyl phenoxy ethoxyethyl dimethylbenzyl ammonium chloride or diisobutyl cresoxy ethoxyethyl dimethylbenzyl ammonium chloride and an alkyl dimethylbenzylammonium chloride, with the alkyl group having from 8 to 18 carbonatoms, such as lauryl-dimethylbenzyl ammonium chloride, provides aparticularly effective and lasting germicidal combination for thearticle of the invention.

In the coating diisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammoniumchloride comprises from 50 to 80% by weight of the total germicidalmaterial and the germicides are preferably added to the elastomer orthermoplastic material in a two batch operation. For example, a firstbatch of the uncured latex or resin is prepared and 1.3 to 10.0% byweight of diisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammoniumchloride and 0.8 to 6.0% by weight of an alkyl dimethylbenzyl ammoniumchloride, based on 100% active ingredients, are then added to the resinand mixed thoroughly therein. Diisobutyl phenoxy ethoxy ethyldimethylbenzyl ammonium chloride is normally used in a weight ratio of1.5 :1 to :1 with respect to the alkyl dimethylbenzyl ammonium chloridein the first batch.

A second batch of the latex or resin of substantially the same weight asthe first batch is prepared and 2.0 to 10.0% of diisobutyl phenoxyethoxy ethyl dimethylbenzyl ammonium chloride and from 0.4 to 4.0% of analkyl dimethylbenzyl ammonium chloride, based on 100% activeingredients, are added to the second batch and thoroughly mixed in.Diisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammonium chloride ispreferably used in a weight ratio of about 3.5:1 to 4.5 :1 with respectto the alkyl dimethylbenzyl ammonium chloride in the second batch. Afterthoroughly mixing the germicidal materials in each separate batch, thetwo batches are combined to provide the final mixture of the latex orresin to be applied to the fabric as a coating by conventionalprocedures. The elastomer coating is then cured by conventional methodssuch as heating the article to a temperature in the range of 300 to 425degrees F.

When using the combination of diisobutyl phenoxy ethoxy ethyldimethylbenzyl ammonium chloride and an alkyl dimethylbenzyl ammoniumchloride as the active germicidal materials, it has been found that theabove two batch mixing procedure is important in providing the desiredgermicidal characteristics in the cured material. The combination ofdiisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammonium chloride andalkyl dimethylbenzyl ammoniuum chloride provides an unexpectedgermicidal activity which cannot be achieved by either germicideseparately. Moreover diisobutyl phenoxy ethoxy ethyl dimethylbenzylammonium chloride appears to remain on or near the surface of thecoating while alkyl dimethylbenzyl ammonium chloride penetrates withinthe coating so that the combination of germicides provides a uniformdistribution of germicidally efiective material throughout the coatingwhich will remain active for long periods.

EXAMPLE NO. 1

As a specific example of the process, 0.3 pound of boric acid, 3.30pounds of diisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammoniumchloride (50% active ingredients) and 2.40 pounds of lauryldimethylbenzyl ammonium chloride (50% active ingredients) were mixedwith 94.0 pounds of polyvinyl chloride resin which was in a thick,paste-like consistency. A second batch was made up by adding 0.3 poundof boric acid, 4.70 pounds of diisobutyl phenoxy ethoxy ethyldimethylbenzyl ammonium chloride (50% active ingredients) and 1.20pounds of lauryl dimethylbenzyl ammonium chloride (50% activeingredients) to 93.8 pounds of polyvinyl chloride resin. Afterthoroughly mixing the separate batches, the two batches were mixedtogether in a vat and the resulting mixture was then applied to onesurface of nylon fabric by a spread-coating process. After the resin hasbeen applied to one surface of the nylon fabric, the coated fabric waspassed through an oven at a temperature of 400 degrees F. to partiallycure the resin. After the precuring treatment, the resin containing thegermicidal materials was applied to the opposite side of the fabric andsubsequently the fabric was passed through a curing oven at atemperature of 400 degrees F. to completely cure the resin coating onboth surfaces.

The germicidal materials were dispersed throughout the resin coating andprovided exceptional effectiveness against various types of bacteria andother micro-organisms for extended periods of time.

EXAMPLE NO. 2

As a second example .10 pound of boric acid, .75 pound of 2 ethylhexanol, 14.917 pounds of diisobutyl phenoxy ethoxy ethyl dimethylbenzylammonium chloride (50% solution) and 8.66 pounds of lauryldimethylbenzyl ammonium chloride (50% solution) were mixed with 75.573pounds of polyvinyl chloride resin which was in a thick paste-likeconsistency. A second batch was prepared by mixing .10 pound of boricacid, .103 pound of 2 ethyl hexanol, 10.917 pounds of diisobutyl phenoxyethoxy ethyl dimethylbenzyl ammonium chloride (50% solution) and 8.66pounds of lauryl dimethylbenzyl ammonium chloride (50% solution). Afterseparately mixing the two batches, the batches were mixed together andthe resulting mixture was applied to nylon fabric as set forth inExample No 1.

The antibacterial activity of the material of the invention isillustrated by the following tests.

Test N0. 1

A sample of the nylon sheeting prepared as in Example No. 1 was cut intoone inch squares and the squares were inoculated by spreading 0.1 ml. ofa 50% serum in saline suspension of Staphylococcus aureus No. 6538 overthe surface of the squares. After an appropriate time interval, thesquares were cultured by shaking in 100 ml. of Difco neutralizing buffersolution. Decimal dilutions of these solutions were plated upon Difcofluid thioglycolate medium containing 1.5 agar. The inoculum was a24-hour nutrient broth culture of the test organism. The test squareswere inoculated with 370,000 organisms. The results of the test are asfollows:

Count per square Sampling time Percent reduction Test No. 1 Test No. 2Average The results of the above test indicate that the sheet materialof the invention reduced the organism count by 99.9% in a four hourperiod.

Test N0. 2

This test was substantially similar to Test No. 1 except that eachsquare was inoculated with 35,000,000 organisms instead of 370,000organisms as in Test No. l. The results of this test are as follows:

Count per square Sampling time Percent reduction Test No. 1 Test No. 2Average 30 Min 23, 000, 000 26, 000, 900 24, 000, 000 31 13, 500, 000 616, 400, 000 82 800, 000 1, 200, 000 97 This test indicates that thesheeting material of the invention was 97% effective in destroying theorganism count in a four hour period, and it is to be noted thatinoculated organism count of 35,000,000 was far greater than that whichwould be present in any hospital, dairy or other sanitary type location.

Test N0. 3

In this test the nylon sheeting prepared as in Test No. 1 was handwashed in detergent and dried 40 times. After this extensive washprocedure the sheeting was cut into one inch square and inoculated as inthe manner of Test No. 1 with 460,000,000 organisms. The antibacterialresults are as follows:

Count per square Sampling time Percent reduction Test No. 1 Test No. 2Average In this test 98% of the Staphylococcus aureus organisms weredestroyed in a four hour period, even though the sheeting had beensubjected to 40 washings prior to the testing.

Test N0. 4

Time of first Ammonia Production, hours Tube number Contents, g.

of fabric To be of practical value for the inhibition of ammonia fromurine, a material must demonstrate a delay of at least 6 hours in theappearance of ammonia production. The samples tested far exceeded therequirements, for there was no evidence of ammonia production in a 24-hour period.

These tests illustrate the effectiveness of the sheeting material incontrolling micro-organisms and reducing bacteria activity. As thegermicidal materials are dispersed within the thermoplastic coating thegermicidal properties will be retained for long periods of time and willnot be impaired by repeated washings.

While the above description is directed to a sheeting material includinga fabric backing, it is contemplated that the thermoplastic material canbe fabricated into articles without the fabric backing. Also, thethermoplastic material can be natural rubber or a thermoplastic resinand can be in a foamed or non-foamed type.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

1 claim:

1. A germicidally treated article, comprising a fabric sheet-likebacking member, a layer of an elastomer bonded to a surface of thebacking member, and finely divided particles of a germicide uniformlydistributed throughout said elastomer, said germicide consistingessentially of 50% to by weight of diisobutyl phenoxy ethoxy ethyldimethylbenzyl ammonium chloride and the balance being an alkyldimethylbenzyl ammonium chloride with said alkyl group having from 8 to18 carbon atoms, said germicide comprising from 5% to 25 by Weight ofthe combined weight of the elastomer and said germicide.

2. A germicidally treated article, comprising a sheet of nylon fabric, alayer of polyvinyl chloride resin bonded to a surface of said fabric,and a germicide distributed throughout the layer of polyvinyl chlorideresin, said germicide consisting essentially of 50% to 80% by weight ofmaterial selected from the group consisting of diisobutyl phenoxy ethoxyethyl dimethylbenzyl ammonium chloride and diisobutyl cresoxy ethoxyethyl dimethylbenzyl ammonium chloride, and the balance being an alkyldimethylbenzyl ammonium chloride with said alkyl group having from 8 to18 carbon atoms, said germicide comprising from 5% to 25% by weight ofthe combined Weight of the elastomer and said germicide.

3. A method of preparing a germicidally treated article, comprising thesteps of preparing an uncured elastomer, mixing a substance selectedfrom the group consisting of diisobutyl phenoxy ethoxy ethyl dimethylammonium halide and diisobutyl cresoxy ethoxy ethyl dimethyl benzylammonium halide, and an alkyl dimethyl-benzyl ammonium halide With saidalkyl group having from 8 to 18 carbon atoms with a quantity of saidelastomer in a weight ratio of 1.5 :1 to 2.5 :1 of said substance tosaid alkyl dimethylbenzyl ammonium halide to provide a first mixedbatch, mixing a material selected from the group consisting ofdiisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammonium halide anddiisobutyl cresoxy ethoxy ethyl dimethylbenzyl ammonium halide, and analkyl dimethylbenzyl ammonium halide with said alkyl group having from 8to 18 carbon atoms with a second quantity of said elastomer in a weightratio of 3.5:1 to 45:1 of said material to said alkyl dimethylbenzylammonium halide to provide a second batch, mixing the first and secondbatches together to provide a combined mixture, applying the mixture toa surface of a backing member in a form of a thin film, and thereaftercuring the elastomer to provide a composite article.

4. A method of preparing a germicidally treated article, comprising thesteps of preparing an uncured elastomer, mixing with a quantity of saidelastomer from 1.3% to 10.0% by weight of diisobutyl phenoxy ethoxyethyl dimethylbenzyl ammonium chloride and from 0.8% to 6.0% by Weightof an alkyl dimethylbenzyl ammonium chloride with said alkyl grouphaving from 8 to 18 carbon atoms to provide a first batch, mixing with asecond quantity of said elastomer from 2.0% to 10.0% by weight ofdiisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammonium chloride andfrom 0.4% to 4.0% by weight of an alkyl dimethylbenzyl ammonium chloridewith said alkyl group having from 8 to 18 carbon atoms to provide asecond batch, mixing the first and second batches together to provide acombined mixture, applying the mixture to a surface of a backing memberin a form of a thin film, and heating the elastomer to cure the same andprovide a composite article having effective and lasting germicidalactivity.

5. A germicidally treated article, comprising an elastomer, and finelydivided particles of a germicidal composition embedded within anduniformly distributed throughout said elastomer, said germicidalcomposition consisting essentially of lauryl dimethylbenzyl ammoniumhalide and a material selected from the group consisting of diisobutylphenoxy ethoxy ethyl dimethyl benzyl ammonium halide and diisobutylcresoxy ethoxy ethyl dimethylbenzyl ammonium halide, said last namedmaterial comprising from 59% to 69% by Weight of the composition thebalance of the composition being said lauryl dimethylbenzyl ammoniumhalide.

6. A germicidally treated article, comprising an elastomer, and finelydivided particles of a germicidal composition embedded within anduniformly distributed throughout said elastomer, said germicidalcomposition consisting essentially of the combination of an alkyldirnethylbenzyl ammonium halide with said alkyl group having from 8 to18 carbon atoms and a material selected from the group consisting ofdiisobutyl phenoxy ethoxy ethyl dimethylbenzyl ammonium halide anddiisobutyl UNITED STATES PATENTS 2,837,462 6/1958 Morin 16784 3,034,9575/1962 Smith et al 16738.5 3,058,877 10/1962 Musser 16738.5 3,058,88110/1962 Wilde 16738.6

JULIAN S. LEVITT, Primary Examiner.

LEWIS GOTTS, FRANK CACCIAPAGLIA, JR.,

Examiners.

1. A GERMICIDALLY TEATED ARTICLE, COMPRISING A FABRIC SHEET-LIKE BACKINGMEMBER A LAYER OF AN ELASTMER BONDED TO A SURFACE OF THE BACKING MEMBER,AND FINELY DIVIDED PARTICLES OF A GERMICIDE UNIFORMLY DISTRIBUTEDTHROUGHOUT SAID ELASTOMER, SAID GERMICIDE CONSISTING ESSENTIALLY OF 50%TO 80% BY WEIGHT OF DIISOBUTYL PHENOXY ETHOXY ETHYL DIMETHYLBENZYLAMMONIUM CHLORIDE AND THE BALANCE BEING AND ALKYL DIMETHYLBENZYLAMMONIUM CHLORIDE WITH SAID ALKYL GROUP HAVING FROM 8 TO 18 CARBONATOMS, SAID GERMICIDE COMPRISING FROM 5% TO 25% BY WEIGHT OF THECOMBINED WEIGHT OF THE ELASTOMER AND SAID GERMICIDE.